Drive devices of the type mentioned above are described in German Patent No. 22 44 793. Here, the interrupter units are realized by the contact pins of low-oil-content circuit breakers, whose movable contact pins in a three-pole embodiment are driven in common by one linear motor.
Further drive devices of the type mentioned above are described in the publication, “Electricity Power Supply, Vol. 96 (1997), Issue 21, pp. 1205 through 1208. Conventional spring mechanisms for the interrupter units, which are made up of a great number of individual mechanical elements, are here replaced by a less expensive, permanently magnetized drive. The movable contact piece of the interrupter unit—here executed as a power switch within a vacuum chamber—is deflected vertically by a so-called coupling shank, the coupling shank being connected to a lever shaft that is coupled from the magnetic drive. The lever shaft is connected to one end of the coupling shank of the interrupter unit, whereas the other end of the coupling shank is controlled by the armature of the magnetic drive. The lifting force of the magnetic drive for actuating the movable contact piece of the interrupter unit is therefore deflected by the lever shaft such that inside the interrupter unit there is a re-deflection in the vertical direction.
In addition to the permanent magnet and the movable armature, the magnetic drive has a closing coil and an opening coil, the closing coil and the opening coil having the sole function of performing a switchover, whereas the generation of retention forces is only achieved by the permanent magnets.